Concentration of ores.



F. J. LYSTER. CONCENTRATION OF ORES.

APPLICATION'FILED JULY'8. I916.

Patented Oct. 31, 1916.

2 SHEETS-SHEET 1.

F. J. L'YSTER.-

CONCENTRATION OF ORES.- APPLICATION FILED JULY 8.1916.

1,203,375 Patented Oct. 31,1916.

2 SHEETS-SHEET 2.

UNITED STATES. PATENT OFFICE...

FLEURY- JAMES LYSTER, OF BROKEN HILL, NEW

SOUTH WALES, AUSTRALIA, ASSIGNOR,

' BY MESNE ASSIGNMENTS, TO MINERALS SEPARATION AMERICAN SYNDICATE (1913) LIMITED, or LONDON, ENGLAND.

CONCENTRATION or onus.

Original application filed May 8, 1913,

' To all-whom it may concern:

Be it' known that I, FLEURY JAMES LYsTnn, subject of the King of Great Britain and Ireland, and residing at 'Broken' Hill, in the State of New South Wales, Commonwealth of Australia, have invented certain new and useful Improvements 'in the Concentration of Ores, of which the following' is a specification, referencebeing had therein to the accompanying drawings, forming part thereof. This invention relates to improvements in the. concentration of ores and is particularly applicable-to the separation of mixed zinc and lead s'ulfid. ores, and this applica tion is a division of my application filed May 8,1913, Serial No. 766,34L6Q The object of this invention is to separate metalliferous portions of an "ore such, for example; as the sulfid of lead (galena) from other portions of the ore, and more particularly to eflect a difli'erentia'l or selective fiotation in the treatment of mixed zinc and lead sultid ores, to wit: the separation'of lead sulfid (galenayf'rom zinc sulfid (blende), obtaining a product relatively rich in lead on the one hand, and a Zinc'product rela1 tively low in lead on the other hand.

I have discovered that sulfid of lead (galena) may be separated from sulfid of zinc (blende) by subjecting the ore or metalliferous materials to a flotationseparation treatment at a low temperature with eucalyptus oil or other frothing agent and with agitation or aeration in an ore pulp containing in solution an alkaline hydrate, for example calcium hydrate, and COntaining in solution a salt of a metal, for example 'cal-. cium sulfate.

The suitability of any given substance in v such a solution can be easily determined by a laboratory test as hereinafter described.

In carrying this process into efiect a plant similar to that employed in andcommon to agitation froth processes may be employed. 1 have shown in the accompanying drawingstwo forms of apparatus adapted for carrying out my process. I

Figure l is a longitudinal elevation and Fig. 2 a cross-section of a unit with the supply devices inelevation, and Fig. 3 is a sec- Specification of Letters Patent Patented Oct. 35,1916.

Serial No. 766,346. Divided and this application maniy 8, 1916. Serial No. 108,209.

tional elevation of an apparatus suitable for testing.

I Wlll now describe my process as carried out inthe apparatus shown in Figs. 1 and 2:

The ore is first ground to a suitable degree of fineness (preferably to slimes so that the dlfferent metallic sulfid particles are disassociated from each other). This finely ground ore with its accompanying circuit '60 water (which is a solution such as hereinbefore described) is led into a settler or thickener A to remove excess water. The thickened pulp is then ledinto a vessel B, from which it passes to the first centrifugal pump C of the series, 0 C C C C G.- These centrifugal pumps are each connected to an individual member of a corresponding series of separating boxes D D D D, D, D.

These centrifugal pumps act as agitators or mixers and means are provided (such as an inlet pipe E) for feeding in the requisite amount of eucalyptus oil or other frothing agent, about 2lbs. per ton of material treated, as well as the requisite amount of air (such as by a tap 11) into the suction pipe G thereof, which is connected to the feed vessel B. The centrifugalpump C draws in' pulp, air, and frothing agent, and produces an intimate mixture which is discharged through the outlet pipe H to the separator box D the delivery of the pump being con-- trolled by the admission of air by the tap F. The particles of lead sulfid (galena) are found to rise to the top of the separator box D, where an inverted pyramid J diverts the froth toward the discharge lip or launder K from which it flows to the receptacle for settling and-collecting the lead concentrate.

The particles which-do not rise or float, to.-

gether with the balance of the water-,sink to the bottom of the box D and are there withdrawn by the outlet pipe L which is connected to the suction pipe G of the next pump C of the series, and the operation is repeated, the residues of the separator box D passing to the centrifugal pump C of the next in series. In the plant illustrated in the accompanying drawings there are six separatonboxes and their attendant pumps,

which comprise one series or unit, but it Willbe understoodthat this number is dependent upon the proportion of mineral contained in the ore and the degree of agitation and aeration required, the repetition of the operations being carried on until the grade of the concentrates becomes too low in lead and the zinc begins to appear therein. The temperature I prefer is below 100 Fah. That is to say, the operation is conducted at the ordinary temperature and no extraneous heat is utilized.

'1 have observed in working the'prooess for the selective flotation of lead sulfids from what are known as calcitic slimes at Broken Hill that an excessive alkalinity tends to retard the selective flotation of the lead sulfid particles. Therefore, when the process isrused with this ore-for this purpose with an alkaline solution, the solution should be onlyslightly alkaline but sufiicient to re spond to the well known methyl orange test.

The suitability of the substances hereinbefore indicated and the proportion thereof to the solution and the degree and duration of agitation or aeration of thematerial treated can be determined in a laboratory test which may be conducted as follows in an apparatussuch as is illustrated in Fig. 3 of the accompanying drawings- This apparatus comprises an agitating or mixing vessel N having a rotating impeller O, a separating box P on the side thereof connected to the mixer by a passage R and by a flexible hose pipe S at the bottom. In carrying out a test the mixing vessel N contains the solution which corresponds with.

the circuit water of the working plant, and eucalyptus or other frothing agent is then added in measured quantities. The impeller O is then rotated at about 1700 revolutions per minute and a charge or about 448 grams of ore is fed in. Sutficient solution is added to fill the separating box P to the level of its discharge lip. The agitated pulp is forced through the passage B into the separating box P and the float or froth rising to the surface is skimmed off over the lip. The pulp is continuously circulated by being drawn from the bottom of the box P by the pipe S back into the mixer N by the action of the impeller O. The flotation is continued until. the float or froth is noticed by observation to become lower in lead and the zinc begins to appear therein. The appearance of the concentrate being skimmed off over to the lip of the separating box will indicate the duration of agitation necessary to obtain a good concentrate combined with a good recovery, while experience will indicate the amount of frothing agent necessary, and further quantities may be added at intervals as found necessary. The residue is run off from the bottom of the machine by disconnecting the flexible hose or pipe S. Repeated trials with different solutions and with diflerent strengths will indicate what meters is best suited to the particular ore under treatment. The ascertained duration of agitation and aeration will govern the number w 1 Calcium hydrate grains per gallon.

8 u u u Calcium sulfate 160 f with Calcium hydrate; 3. 6 f

Calcium nitrate s 300 with Calcium hydrate 1. 8 Calcium nitratc 300 with Calcium hydrate; 3. 6 Calcium nitrate 300 with Calciui hydrate 18 Magnesium sulfate 400 with Calcium hydrate; 1. 8 Magnesium sulfate 400 with Calcium hydrate 3. 6 Magnesium sulfate 400 with Calcium hydrate 18 Magnesium nitrate 300 with .Calcium hydrate 1. 8 Magnesium nitrate 300 with Calcium hydrate 3. 6 Magnesium nitrate c 300 with Calcium hydrate 18 Potassium sulfate 300 with Calcium hydrate 1. S Potassium nitrate 400 with Calcium hydrate 1. S Potassium nitrate 400 with Calcium hydrate 18 Sodium sulfate s00 with Calcium hydrate 1.8 Sodium sulfate 800 with Calcium hydrate 3. 6 Sodium sulfate 800 with Calcium hydrate 18 I have further discovered that the residues obtained as before described containing the bulk of the zinc sulfids may be further treated by flotation separation to produce a concentrate rich in zinc by first dewatering and thickening -the pulp and then submitting it to a, repetition of the flotation-separation, using, however, su ficient water in lieu of.the solution previously employed. or by further continuing the process hereinbefore described, after the recovery of the lead sulfids (galena) in a separate dezincing unit until the zinc sulfids (blende) appear upon the surface of the solution and are carried over into the In the following claims I have designated I the alkaline hydrate'and the salt of a metal and an alkaline hydrate as being present in solution in the pulp'inj abnormal amounts, meaning that these agents are employed .in amounts exceeding their ordinary negligible proportions innatural water, and sufficient to modify or influence the selectivity of the froth flotation.

Iclaim:

1. A process of concentrating ores which consists in agitating and aerating an orepulp, containing in solution an alkalinehydrate inabnormalamount such as to act as a selectivity modifying agent, so as to obtain a froth of concentrates, and separating the froth. i

2. A process of concentrating ores which consists in agitating and aerating an ore pulp, containing a ,small proportion of a frothing agent and contaming in solution an alkaline hydrate in abnormal amount such as to act as a selectivity modifying agent, so as to obtain a froth of concentratesf and separating the froth.

3. A process of'concentrating ores which consists in. agitating pulp, containing in solutiona salt of a metal amounts such as to modify selectivity, so as to obtain a froth of concentrates, and separating the froth.

4. A process of concentrating ores which consists in agitating and aerating an ore pulp, containing a small proportion of a frothing agent and containing in solution a salt of a metal and an alkaline hydrate in abnormal amounts such as to modify selectivity, so as trates, and separating the froth.

. 5. A process of concentrating ores which consists in agitating and aerating an ore pulp, containing calciumv hydrate in solution in an abnormal amount sufiicient to act as a selectivity modifying agent, so as to obtain a froth of concentrates, ing the froth.

6. A process of concentrating ores which consists in agitating and aerating an ore pulp, containing a small proportion of a frothing agentyanjd containing in solution an abnormal amount of calcium hydrate suflicient to modify selectivity, so as to obtain a froth of concentrates, and separating the froth.

7 A process of concentrating ores which consists in agitating and aerating an ore by gravitation or tables and an alkaline hydrate amounts sufficient to modify selectivity, so

. pulp,

and aerating an ore in abnormal to obtain a froth of concen-- and separat 'suflicient to modify selectivity, so as to obtain a froth of concentrates, and separating.

the froth.

8. A process of concentrating ores which consists in agitating and aerating an ore pulp, containing a small proportion of a frothing agent and containing in solution a salt of ametal andcalcium hydrate in abnormal amounts sufficient to modify selectivity, so as to obtain a froth of concentrates, and separating the froth.

9.-A process of concentrating ores which consists in' agitating and aerating an ore pulp, containing in solution calcium sulfate in abnormal as 'to obtain a froth of concentrates, and separating the froth.

10. A process of concentrating ores which consists'in agitating and aerating an ore pulp, containing a small proportion of a, frothing agent and containing in solution calcium sulfate and analkaline hydrate in abnormal amounts sufli'cient to-modify selectivity, so as to obtain a froth of concentrates, and separating the froth.

11. A process of concentrating ores which consists in agitating and aerating an orecontaining calcium sulfate and calcium hydrate insolution in abnormal amounts sufiicient to modify selectivity, so as to obtain a froth of concentrates, and separating the froth.

12. A process of concentrating ores which consistsin agitating and aerating an, ore pulp, containing a small proportion of a frothing agent and containing in solution calcium sulfate and calcium hydrate in abnormal amounts sufficient to modify selectivity, so as to obtain a froth of concen-. trates, and separating the froth.

13. A process for the separation of lead sulfids from zinc sulfids in an ore containing 1 mixed lead and Zinc sulfidswhich consists in subjecting such an ore to the agitation froth process by agitation in a. pulp, solution an abnormal amount of an alkaline hydrate sufiicient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating the froth.

14. A process for the separation of lead sulfids from zinc sulfids in an ore containing containing in t mixedlead and Zinc'sulfids which consists in subjecting such an ore to the agitation froth process by agitation in a pulp, containing a small proportion of a frothing agent andcontaining in solution an alkaline hydrate in an abnormal amount sufficient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating the froth.

15. A process for the separation of lead mixed lead and zinc sulfidswhich consistsinsubjecting such an ore to the agitation froth process by agitation in a pulp, containing a small proportion of a frothing agent. and containingin solution a salt of a metal and an alkaline hydrate in abnormal amounts sufficient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating the froth. I j

17. A process for the separation of lead sulfids from zinc sulfids in an ore containing mixed lead and zinc sulfids which consists in subjecting such an ore to'the agitation froth process by agitation in a pulp, containing in solution an abnormal amount of calcium hydrate sufficient to modify selectivity, so as to obtaina froth of concentrates wherein the lead sulfids predominate, and separating the froth. v

18. A process for the separation of lead sulfids from zinc sulfids in an ore containing mixed lead and zinc sulfids which 0on sists in subjecting such an ore to the agitation froth process by agitation in a pulp, containinga small proportion of a frothing agent and containing in solution an abnormal. amount of calcium hydrate sufficient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating the froth,

19. A process for the separation of lead sulfids from nine sulfids in an ore containing mixed lead and zinc sulfids which consists in subjecting such an ore to the agitation froth process by agitation in a pulp,

containing in solution a salt of a metal and calcium hydrate in. abnormal amounts sufficient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating the froth. 20. A process for the separation of lead sulfids from zinc sulfids in an ore containing mixed lead and zinc sulfids which consists taining a small'proportion of a frothing mosses agent and containing in solution a salt of a metal and calcium hydrate in abnormal amounts sufficient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating A process for the separation of lead sulfids from zinc sulfids in an ore contain ing mixed lead and zinc sulfids which consists in subjecting such an. ore to the agitation froth process by agitation in apulp, containing a small proportion. of ial'f-rothing agent and containing in solution calcium sulfate and analkaline hydrate in abnormal amounts sufficient to modify selectivity, so

as to obtain a froth of concentrates wherein"- the lead sulfids predominate, and separating the froth.

23. A process for the separation of lead sulfids from zinc sulfids in an ore containing mixed lead and zinc sulfids which consists in subjecting such an ore to the agitaf.

tion froth process by agitation in a pulp, containing calcium sulfate and calcium hydrate in solution in abnormal amounts sufiicient to modify selectivity, so as to obtain a froth of concentrates wherein the lead sulfids predominate, and separating froth.

24;. A process for the separation of lead the sulfids from zinc sulfids in an ore containing mixed lead and zinc sulfids'which consists in subjecting such an ore tothe agitation froth process by agitation in a pulp, containing a small proportion of a frothing agentand containing in solution abnormal amounts of calcium sulfate and calcium hydrate sufiicient to modify selectivity, so as to obtain a froth of concentrates wherein the leadsulfids predominate, and separating the froth.

In testimony whereofI have aflixed my signature.

a FLEURY J'Auns LYSTER.

Witnesses ARTHUR GORE COLLISON, FLORENCE MANTHERPE. 

